The analysis of neuroanatomical information is a labor-intensive process which is usually limited by the stamina of the investigators. Limitations on the latter may lead to either a decrease in the quantity of tissue analyzed or a degradation in the quality of the analysis, or to both. It is now possible using computer-based techniques to increase productivity, in the number and quality of neuroanatomical images generated. Furthermore, the integration of such images into three-dimensional reconstructions which can be readily manipulated to yield the clearest possible representation of findings is a new capability made available by computer technology. The present proposal is to apply a powerful neuroanatomical image handling system in the context of four ongoing research efforts; 1. a study of the integration of central pain, analgesic, and autonomic mechanisms in the mammalian brain (Drs. Koh and Kream); 2. a study of mechanisms of central opioid analgesia, using an animal model of stress analgesia (Drs. Thompson, Koh, Miczek, and Shuster); 3. a study of hypothalamic structure and function, including mechanisms of ovulatory control, and the generation of circadian rhythms in the human hypothalamus (Drs. Stopa and King), and 4. a study of the organization of olfactory processing in the amphibian brain, using 2-deoxyglucose autoradiographic and intracellular staining techniques (Drs. Hamilton and Kauer). The following discussion will describe a new image analysis system which has been designed for use in high-resolution neuroanatomical work, and present the particular merits of the system as applied to each of the four project areas listed above.